**To describe valid modifications for a DB instance**

This example describes the valid modifications for a DB instance (*test-instance*)::

    aws rds describe-valid-db-instance-modifications --db-instance-identifier test-instance

Output::

{
    "ValidDBInstanceModificationsMessage": {
        "ValidProcessorFeatures": [],
        "Storage": [
            {
                "StorageSize": [
                    {
                        "Step": 1,
                        "To": 20,
                        "From": 20
                    },
                    {
                        "Step": 1,
                        "To": 6144,
                        "From": 22
                    }
                ],
                "ProvisionedIops": [
                    {
                        "Step": 1,
                        "To": 0,
                        "From": 0
                    }
                ],
                "IopsToStorageRatio": [
                    {
                        "To": 0.0,
                        "From": 0.0
                    }
                ],
                "StorageType": "gp2"
            },
            {
                "StorageSize": [
                    {
                        "Step": 1,
                        "To": 6144,
                        "From": 100
                    }
                ],
                "ProvisionedIops": [
                    {
                        "Step": 1,
                        "To": 40000,
                        "From": 1000
                    }
                ],
                "IopsToStorageRatio": [
                    {
                        "To": 50.0,
                        "From": 1.0
                    }
                ],
                "StorageType": "io1"
            },
            {
                "StorageSize": [
                    {
                        "Step": 1,
                        "To": 20,
                        "From": 20
                    },
                    {
                        "Step": 1,
                        "To": 3072,
                        "From": 22
                    }
                ],
                "ProvisionedIops": [
                    {
                        "Step": 1,
                        "To": 0,
                        "From": 0
                    }
                ],
                "IopsToStorageRatio": [
                    {
                        "To": 0.0,
                        "From": 0.0
                    }
                ],
                "StorageType": "magnetic"
            }
        ]
    }
}

